Thermostatic circuit controller



Oct. 4, 1932. M. TRAPP THERMOSTATIC CIRCUIT CONTROLLER Filed March 9,1928 A TTORNEY.

Patented Oct. 4, 1932 UNITED STATES MARTIN TRAPP, F IBELZONI,MISSISSIPPI THERMOSTATIC CIRCUIT CONTROLLER Application filed March 9,

The invention relates to thermostats and more especially to athermostatic circuit controller of a type adapted to be used inconnection with an electric motor to energize said motor at a.predeterminate degree of temperature, whereby the motor is rotated inone direction, and to energize the motor also at a second predeterminatedegree of temperature in order to rotate said motor in the oppositedirection.

The object of the invention therefore is to provide a thermostat havingthree electrical terminals, two whereof are arranged on adjustable handsor the like, the third terminal being electrical connected with athermometer hand, which is adapted to change its position relative tothe other hands under the influence of a bi-metal spring supporting saidthermometer hand and in electrical connection with the third terminal.

Other objects of the invention not specifr cally mentioned will beeasily ascertained and understood from the following description inconnection with the accompanying drawing forming a part thereof. It ishowever to be noted, that the invention is not to be limited orrestricted to the exact construction or formation shown in the drawingand described in the specification, but that the invention is only to belimited by the scope of the claim appended hereto.

In the drawing illustrating a preferred embodiment of the invention.

Fig. 1 is a front view of the invention, and

Fig. 2 is a sectional side view thereof.

The thermostat has a face plate 5. On this plate a scale 6 of thedegrees of temperature is arranged in any suitable and desired manner.The plate may be provided with ears 7 for fastening the thermostat to awall or the like. A triangular carrier plate 8 is fastened underneaththe face plate5 by means of studs 9 or the like and is held spaced fromsaid face plate. A bimetal spring is fastened to the carrier plate withits inner end and carries at its outer end a thermometer hand 11. Thishand may be fastened to said spring by a pin 12 or in any other suitablemanner. 60 An electric terminal 13 is provided on the 1928. Serial No.260,522.

face plate 5 and a wir; it leads from said terminal to a source ofelectricity.

A pin 15 or the like is fastened in the face plate in such a manner,that the axis of said pin and the axis of the bi-metal spring coincidc.

A hand 16 is pivotally mounted on the pin 15 and is insulated therefromas indicated at 17. Another hand 18 is also pivotally mounted on thesame pin and is also insulated thercfrom as indicated at 19. The outerends 20 and 21 respectively of the hands 16 and 18 are made of separatepieces of metal and insulation members 22 and 23 respectively connectthe parts of each hand with each other. A contact plate 24 and 25respectively extends at right angles from each 01' the outer ends 24 and25 respectively, and terminals 26 and 27 respectively are provided onsaid ends. Electric conductors 28 and 29 respectively 7 lead from saidterminals to an electric motor (not shown).

The thermometer hand 11 has its outer end curved toward the face plateand carries a contact link 30.

Supposing the thermostat is to be used to protect a pipe line fromfreezing. For this purpose a main valve-would be provided in the main ofsaid pipe .ine and a motor would be connected mechanically with saidvalve to open and close the same in accordance with the temperature. Themotor is of the reversible type and connected with the source ofelectricity and with the terminals 26 and 27 of the thermostat hands.The terminal 13 is also electrically connected with the source ofelectricity.

The hands 16 and 1.8 are set to the degrees of temperature, at which themain valve is to be closed and opened respectively. When it gets colderthe thermometer hand 11 will mo,ve toward the left in Fig. 1 under theinfluence of the bi-metal spring 10. The link 30 will contact firstwith'the plate 25 of the thermostat hand 18. The valve being open andthe motor being in reverse the closing of the contact between the linkand said plate will cause no rotation of the motor or any other change.lVhen it gets still colder the link will contact with the plate 24 ofthe hand 16. Thereby the circuit from the source of I electricity toterminal 13, face plate 5, pins 9, triangular plate 8, bimetal spring10, thermometer hand 11, link 30, plate 24, outer end 20, terminal 26conductor 28 to the motor and back to the source of electricity will beclosed.

The motor will be energized, will rotate and close the main Valve and atthe same time the olarization of the motor will be reversed.

n consequence the motor will now stand still until it gets Warmer andthe ther hand will travel toward the right inFig. 1, whereby the link 30will come in contact with the plate 25 closing the circuit andenergizing the motor, which will then open the main valve and againreverse its own polarization.

It is understood that the above described.

thermostat may be used for all kinds of other purposes, for instance toconnect a fire alarm gong with a source of electricity, when a certaindegree of heat should occur in a dwelling or the like.

What I claim as new is In a device of the class described a metal faceplate, an electric terminal thereon, a

bimetal metal sprin supported by said plate, a thermometer han fastenedto said spring, a plurality of metal hands adjustably supported by saidplate and insulated therefrom and in relation to each other, an electricterminal on each of-said hands, a contact plate on each of said handsthe thermometer hand being provided with an eye, and a metal springhanging in said eye, and adapted to contact with the contact plateswhile sliding over the same.

In witness whereof I alfix my signature. MARTIN TRAPP.

